Combustion 4 Problems or adjustments

hi all,
I have Combustion 4 here and working-learning for very small projects,
now i have BIG project and some problems,

I have PC,
XP pro,
2giga RAM,
FX5500,
P4 3.00Ghz,
120G free space on HD

now im Animate some Pictures (scanned one from painting) *.Tiff fils , 2200 X 2500 , best Quality... to a simple 24 seconds (!) and using 2 layers or just one, making some effects... nothing serious just trying it with the big pictures...

the main thing is that if i'm rendering the movie at preview it take some time - very low quality and its hard to see the details, so trying to render at Best quality it moves Very SLOW...

and if im adding one more picture or some more effects and changes, the program just hang for while... so i cant really able to work...

no anti-virus, no Internet, no office - nothing just XP and this program and still having the problem.

in Windows Task Manager i can see that in rendering the CPU is like 75 and the memory usge is about 170,000... is that OK?

is it possiable that the computer is need more Memory?
is it just system definition?
is it the program definition?

thank you all...

Alpako.